Re: [PATCH v2 02/26] selftests/resctrl: Split fill_buf to allow tests finer-grained control

From: Ilpo Järvinen
Date: Thu Dec 07 2023 - 09:04:15 EST


On Tue, 28 Nov 2023, Reinette Chatre wrote:
> On 11/20/2023 3:13 AM, Ilpo Järvinen wrote:
> > MBM, MBA and CMT test cases call run_fill_buf() that in turn calls
> > fill_cache() to alloc and loop indefinitely around the buffer. This
> > binds buffer allocation and running the benchmark into a single bundle
> > so that a selftest cannot allocate a buffer once and reuse it. CAT test
> > doesn't want to loop around the buffer continuously and after rewrite
> > it needs the ability to allocate the buffer separately.
> >
> > Split buffer allocation out of fill_cache() into alloc_buffer(). This
> > change is part of preparation for the new CAT test that allocates a
> > buffer and does multiple passes over the same buffer (but not in an
> > infinite loop).
> >
> > Co-developed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> > Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> > ---
>
> Could you please list the changes to a patch in this area instead of
> lumping all in the cover letter? Without this it is not clear what,
> if anything, changed in the new version.

Okay, I'll try to keep them per patch.

> > +static int fill_cache(size_t buf_size, int memflush, int op, bool once)
> > +{
> > + unsigned char *buf;
> > + int ret;
> > +
> > + buf = alloc_buffer(buf_size, memflush);
> > + if (!buf)
> > + return -1;
> > +
> > if (op == 0)
> > ret = fill_cache_read(buf, buf_size, once);
> > else
> > ret = fill_cache_write(buf, buf_size, once);
> > -
> > free(buf);
> >
> > - if (ret) {
> > - printf("\n Error in fill cache read/write...\n");
> > - return -1;
> > - }
> > -
>
> The changelog does not motivate the removal of this error message.
> It seems ok at this point since the only failing functions already
> print their own error message. Without a motivation of this change
> it is not clear if it is actually intended.

Hi,

I don't have recollection of how it ended up into this patch as it's so
long time ago already... But in any case, it naturally seemed to fit into
the next patch that removes the extra call level so I moved the removal
of the duplicated error printout to that patch instead.

> In any case, this looks good.
>
> Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>


--
i.